<html>
    <head>
        <script type="text/javascript">
            var c=0;
            var t;
            var timer_is_on=0;

            function timerCount(pagina)
            {
                checkinfo(pagina);
                t=setTimeout("timerCount()",30000);
            }

            
            function funcionCallback(){
            if( ajax.readyState == 4 )
            {
                if( ajax.status == 200 )
                {

                }
            }
        }

        function checkinfo(pagina){
                if( window.XMLHttpRequest )
                    ajax = new XMLHttpRequest();
                else
                    ajax = new ActiveXObject("Microsoft.XMLHTTP");
                ajax.onreadystatechange = funcionCallback;
                ajax.open( "POST", "/Drinkmeter/Background?page="+pagina, true );
                ajax.send( "" );
            
            }
        
            
        </script>
    </head>

    <body>
        <form>
            <input type="button" value="Start count!" onclick="timerCount()">
            <input type="text" id="txt" />
        </form>
    </body>
</html>